Electronic devices may include a range of different touch-sensitive input surfaces, for example as incorporated into displays, track pads, keyboards, and combinations thereof. In use, however, oils and other deposits may affect appearance and performance, particularly where information is also displayed on the touch-sensitive surface (e.g., on a touch-sensitive display).
To address this problem, a number of different surface treatments are available, depending on substrate design and desired composition. Different surface treatments, however, may also exhibit different performance criteria, and not all surface treatments are compatible with all substrate materials. Thus, the issue of surface treatment raises a number of different design challenges, particularly for touch-sensitive surfaces subject to a range of different environmental conditions and operational demands.